Earl a Category 4 storm again

Hurricane Earl has regained Category 4 strength this afternoon, and continues on a steady northwest path towards the North Carolina coast. Recent satellite imagery shows that Earl has become more symmetrical, with improved upper-level outflow and no signs of dry air wrapping into the core. The improved appearance is probably due to lower wind shear. Latest wind shear tendency imagery from the University of Wisconsin CIMSS group shows that shear on the southwest side of Earl has fallen by about 10 knots over the past 24 hours.

Figure 1. Afternoon satellite image of Earl.

Forecast for EarlThe latest set of model runs from 8am EDT (12Z) this morning shows little change to Earl's track. Thus, my write-up of the possible impacts to North Carolina, New England, and Canada in this morning's post remain unchanged. The latest SHIPS model forecast shows wind shear will remain moderate, about 15 knots, through Friday afternoon. This should allow Earl to maintain major hurricane status as it passes North Carolina early Friday morning. By Friday night, as Earl gets caught in the jet stream and accelerates to the northeast, wind shear will rise to 20 - 30 knots and ocean temperatures will plunge to 20°C, resulting in considerable weakening. Earl will still probably be a Category 1 or 2 hurricane early Saturday morning, when it will make its closest approach to New England. Earl is more likely to be a strong tropical storm or weak Category 1 hurricane early Saturday afternoon, when it is expected to make landfall in Nova Scotia, Canada.

Earl is a large hurricane, which gives it a higher potential for storm surge damage than a smaller hurricane with the same top winds. One measure of a storm's power, useful for gauging storm surge threat, is to measure the speed of the winds and multiply by the area over which those winds blow. This total is called the Integrated Kinetic Energy (IKE). Based on the storm's IKE, one can come up with a scale from 0 - 6 rating the storm's destructive power from its storm surge. A separate rating can be given to the destructive potential of the storm's winds. The IKE value of 112 Terrajoules for Earl, at 3:30pm EDT today, gives its storm surge a destructive power of 5.0 on a scale of 0 - 6. Earl's winds have a lower destructive power, 3.4 on a scale of 0 - 6. Let's hope the right front quadrant of Earl, where the main storm surge would occur, stays offshore! For comparison, the small Category 5 Hurricane Camille of 1969 had an IKE of 80 Terrajoules, and the very large Category 2 Hurricane Ike of 2008 had an IKE of 116 Terrajoules--similar to Category 3 Earl's.

FionaTropical Storm Fiona is struggling due to high wind shear, courtesy of strong upper-level northerly winds from Hurricane Earl's outflow. The latest Hurricane Hunter center fix at 1:29pm EDT found Fiona had weakened some, with a central pressure of 999 mb. This is a rise of 1 mb from this morning. The wind shear analysis from the University of Wisconsin CIMSS group shows that shear has increased to a moderately high 15 - 20 knots this afternoon. Satellite loops show the classic signature of a tropical storm experiencing high wind shear--an exposed center of circulation, and all the heavy thunderstorms pushed to one side (the south side in this case). Martinique radar shows that the outer bands from Fiona are bringing heavy rain squalls to the same islands of the northern Lesser Antilles that were affected by Earl. Our wundermap for the northern Lesser Antilles shows no stations recorded winds over 20 mph this afternoon, though there was no reporting station on Barbuda, the island closest to Fiona.

Forecast for FionaModerate wind shear and dry air should keep Fiona from attaining hurricane status over the next two days, as big brother Earl continues to bring high wind shear. The shear may be strong enough to destroy Fiona, as predicted by the NHC. However, by this weekend, Earl may pull far enough away for shear to drop and Fiona to survive. The 4 - 5 day track forecast is highly uncertain, as there is a large spread in the model solutions. It is possible Fiona may pose a threat to Bermuda on Saturday or Sunday, and the storm could wander for a week or more in the waters between Bermuda and the U.S. East Coast.

Figure 2. Afternoon satellite image of Fiona.

Tropical Storm Gaston formsTropical Storm Gaston developed enough heavy thunderstorms near its center this afternoon to get a name, and appears destined to become Hurricane Gaston by early next week. Water vapor satellite images show a large area of dry air to the north and west of Gaston, and this dry air will be the dominant inhibiting factor for development. The latest SHIPS model forecast predicts shear will remain moderate, 10 - 15 knots, for the next four days, and perhaps fall to the low range 4 - 5 days from now. Gaston is over warm 28°C waters, and should be able to steadily intensify into a hurricane by Saturday or Sunday, as predicted by the many of the intensity models. Gaston may threaten the northern Lesser Antilles Islands as early as Tuesday.

Next postI'll have an update in the morning, and Dr. Rob Carver will have a late night update tonight.

Quoting NewportWaterman:I hate it when soccer moms get all uppity..looking at you Chicklit...Stop worrying about people surfing in high seas. Just because you can't do it does not mean we should not. Go back to your PTA or garden club meeting and stop trash talking. 99% of the people who die during high surf are future recipients of a Darwin award and probably should not have been near the beach in the first place...

I imagine in the 11PM discussion we'll get an upgrade in winds by 5-10knots, and the standard boilerplate along the lines of "Earl may attain Category 5 status but these things are too uncertain to predict and due to fluctuations in eyewall structure". What else can they say?

Quoting CloudGatherer:I think at 11PM, the NHC is going to start hitting the panic button. We've got a perfect-looking storm. Its pressure has dropped to 931MB, and although the surface-level winds haven't caught up, the velocities not far above the surface are terrifying. With warm water still ahead, and landfall not imminent, there's more than enough time for Earl to bring those winds down to the surface, and become a strong Cat4 or a Cat5. CIMSS - which lags by about an hour - is now spitting out an adjusted T# of 6.5, which would support 127 knot winds. An hour from now, when it takes the storms present appearance into account, that number will be close to 7, if not slightly above it. And that's Cat 5, boys and girls.

The nightmare for the NHC isn't crying wolf; it's failing to warn of a potentially catastrophic event in sufficient time for political leaders to act on those warnings. When Earl was a Cat 3, the NHC was willing to stand by its models. When they elevated it to Cat 4 at 5PM, even though the tracks hadn't much changed, they issued all sorts of warnings and watches - you don't mess around with a Cat 4 storm. And whatever margin of error remained has now entirely vanished. We're going to see the tropical storm warnings upgraded to hurricane warnings, and the TS watches switched over to hurricane watches. The track is going to be bent a little west, just to put the fear of Earl in people, so they'll take the necessary precautions. And, yeah, we'll see the intensity upgraded - 130kts wouldn't shock me, although 125kts is more likely.

Been pretty busy today, so I haven't had a chance to get on the blog. I was wondering why the NHC was so against now Gaston yesterday. His structure was very good when they only had him at 10% and I, along with others one here, were commenting about how conditions ahead would be optimal for further strengthening. Gaston is a perfect example of how the NHC goes by the models too much most of the time as the models were not showing development of him at all. Glad they went ahead and put a circle around the one exiting Africa because it too should have the same conditions for development.

And about Earl- All I can say is WOW. I sure hope he stays offshore...wobbles one way or the other will be significant now that he's so close. Let's hope for wobbles to the right, although he is wobbling left currently...

Rt 12 almost always washes out and gets inpassable. They usually have to get the backhoes out to get the sand off the road. Two lane road between miles of sand dunes. We're a bit better off down this end.

Quoting CloudGatherer:I think at 11PM, the NHC is going to start hitting the panic button. We've got a perfect-looking storm. Its pressure has dropped to 931MB, and although the surface-level winds haven't caught up, the velocities not far above the surface are terrifying. With warm water still ahead, and landfall not imminent, there's more than enough time for Earl to bring those winds down to the surface, and become a strong Cat4 or a Cat5. CIMSS - which lags by about an hour - is now spitting out an adjusted T# of 6.5, which would support 127 knot winds. An hour from now, when it takes the storms present appearance into account, that number will be close to 7, if not slightly above it. And that's Cat 5, boys and girls.

The nightmare for the NHC isn't crying wolf; it's failing to warn of a potentially catastrophic event in sufficient time for political leaders to act on those warnings. When Earl was a Cat 3, the NHC was willing to stand by its models. When they elevated it to Cat 4 at 5PM, even though the tracks hadn't much changed, they issued all sorts of warnings and watches - you don't mess around with a Cat 4 storm. And whatever margin of error remained has now entirely vanished. We're going to see the tropical storm warnings upgraded to hurricane warnings, and the TS watches switched over to hurricane watches. The track is going to be bent a little west, just to put the fear of Earl in people, so they'll take the necessary precautions. And, yeah, we'll see the intensity upgraded - 130kts wouldn't shock me, although 125kts is more likely.

If they don't sound the alarm at 11 PM, they won't. It'll be too late.

Quoting VBgirl:I'm in Kill Devil Hills on vacation at parents beach house. There is a part of me that really, really wants to stay. Not leaving unless they evacuate residents. We are between the beach road and the bypass.

No offense, but you're crazy. I've only been through Ike, but if you are that close to the beach... yeah, I would be on the way out right now.

I think at 11PM, the NHC is going to start hitting the panic button. We've got a perfect-looking storm. Its pressure has dropped to 931MB, and although the surface-level winds haven't caught up, the velocities not far above the surface are terrifying. With warm water still ahead, and landfall not imminent, there's more than enough time for Earl to bring those winds down to the surface, and become a strong Cat4 or a Cat5. CIMSS - which lags by about an hour - is now spitting out an adjusted T# of 6.5, which would support 127 knot winds. An hour from now, when it takes the storms present appearance into account, that number will be close to 7, if not slightly above it. And that's Cat 5, boys and girls.

The nightmare for the NHC isn't crying wolf; it's failing to warn of a potentially catastrophic event in sufficient time for political leaders to act on those warnings. When Earl was a Cat 3, the NHC was willing to stand by its models. When they elevated it to Cat 4 at 5PM, even though the tracks hadn't much changed, they issued all sorts of warnings and watches - you don't mess around with a Cat 4 storm. And whatever margin of error remained has now entirely vanished. We're going to see the tropical storm warnings upgraded to hurricane warnings, and the TS watches switched over to hurricane watches. The track is going to be bent a little west, just to put the fear of Earl in people, so they'll take the necessary precautions. And, yeah, we'll see the intensity upgraded - 130kts wouldn't shock me, although 125kts is more likely.

Quoting VBgirl:I'm in Kill Devil Hills on vacation at parents beach house. There is a part of me that really, really wants to stay. Not leaving unless they evacuate residents. We are between the beach road and the bypass.

Have you looked at the latest satellite image of Earl ?. Probably not.

Quoting VBgirl:I'm in Kill Devil Hills on vacation at parents beach house. There is a part of me that really, really wants to stay. Not leaving unless they evacuate residents. We are between the beach road and the bypass.

Be careful! I know some folks down there on vacation. They're not leaving unless mandatory evac is required. They're on Rt 12.

Quoting VBgirl:I'm in Kill Devil Hills on vacation at parents beach house. There is a part of me that really, really wants to stay. Not leaving unless they evacuate residents. We are between the beach road and the bypass.

Quoting VBgirl:I'm in Kill Devil Hills on vacation at parents beach house. There is a part of me that really, really wants to stay. Not leaving unless they evacuate residents. We are between the beach road and the bypass.

I'm in Kill Devil Hills on vacation at parents beach house. There is a part of me that really, really wants to stay. Not leaving unless they evacuate residents. We are between the beach road and the bypass.